import java.util.Scanner;
public class Text2 {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int num = sc.nextInt();
        boolean flag = true;

        for(int i = 2;i < num;i++) {
            if(num % i  == 0) {
                flag = false;
                break;
            }
        }
        if(flag) {
            System.out.println(num + "是一个质数");
        } else {
            System.out.println(num + "不是一个质数");
        }

    }
}
